Abstract: Disclosed is a method comprising transmitting a first signal, obtaining an indication of a harmonic, wherein the harmonic is caused by the transmission of the first signal, determining, based on the indication of the harmonic, an estimation of the harmonic, receiving a second signal, wherein the second signal comprises the harmonic, and subtracting the estimation of the harmonic from the second signal.

Abstract: An apparatus includes an estimation circuitry configured to receive a first set of one or more digital signals of transmitters of a communication system, and capture a set of one or more radio frequency signals that have been generated from the first set of digital signals The set of radio frequency signals being input of an antenna system of the communication system. Based on the first set of digital signals and the corresponding set of radio frequency signals, a set of weights related to a distortion effect caused by the generation of the radio frequency signals is derived. A received second set of digital signals is weighted using the set of weights, resulting in filtered signals. Using the filtered signals, a correction signal indicative of an interference caused by transmission of the second set of digital signals at a receiver of the communication system is estimated.

Abstract: The present subject matter relates to an apparatus for a communication system. The communication system comprises transmitters being configured to operate in multiple transmission frequency bands. The apparatus comprises means being configured for: capturing a set of over-the-air signals at distinct frequency bands of the multiple transmission frequency bands; aligning in time the set of signals using delays between the set of signals and a received signal at a selected receiver of the communication system; combining the set of aligned signals to generate a composite signal; and estimating an interference signal that is caused by the set of signals at the selected receiver by weighting the composite signal using a set of one or more calibrated parameters for the estimation.

Abstract: An apparatus includes an estimation circuitry configured to receive a first set of one or more digital signals of transmitters of a communication system, and capture a set of one or more radio frequency signals that have been generated from the first set of digital signals The set of radio frequency signals being input of an antenna system of the communication system. Based on the first set of digital signals and the corresponding set of radio frequency signals, a set of weights related to a distortion effect caused by the generation of the radio frequency signals is derived. A received second set of digital signals is weighted using the set of weights, resulting in filtered signals. Using the filtered signals, a correction signal indicative of an interference caused by transmission of the second set of digital signals at a receiver of the communication system is estimated.

Abstract: To take into account a passive intermodulation, resource blocks are associated with information indicating passive intermodulation impact of a corresponding resource block. The resource blocks are scheduled using the information.

Abstract: To take into account a passive intermodulation, resource blocks are associated with information indicating passive intermodulation impact of a corresponding resource block. The resource blocks are scheduled using the information.

Abstract: The present invention addresses method, apparatus and computer program product for stabilization of the direct learning algorithm for wideband signals. Thereby, a signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier, and the pre-distorted output signal from the pre-distorter is forwarded to the power amplifier. Parameters of the pre-distorter are adapted based on an error between the linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm, and the linear system of equations formed by the direct learning algorithm are solved using a conjugate gradient algorithm, wherein, once per direct learning algorithm adaptation, at least one of the initial residual and the initial direction of the conjugate gradient algorithm are set based on the result of the previous adaptation.

Abstract: The present invention addresses method, apparatus and computer program product for controlling a Direct Learning Algorithm. Thereby, a power amplifier operating in a non-linear state is controlled. A signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier. The pre-distorted output signal is forwarded from the pre-distorter to the power amplifier. Parameters of the pre-distorter are adapted in plural steps based on an error between a linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm. It is detected whether the error diverges; and adapting of the parameters of the pre-distorter is stopped when it is determined that the error is diverging.

Abstract: The present invention addresses method, apparatus and computer program product for stabilization of the direct learning algorithm for wideband signals. Thereby, a signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier, and the pre-distorted output signal from the pre-distorter is forwarded to the power amplifier. Parameters of the pre-distorter are adapted based on an error between the linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm, and the linear system of equations formed by the direct learning algorithm are solved using a conjugate gradient algorithm, wherein, once per direct learning algorithm adaptation, at least one of the initial residual and the initial direction of the conjugate gradient algorithm are set based on the result of the previous adaptation.

Abstract: The present invention addresses method, apparatus and computer program product for stabilization of the direct learning algorithm for wideband signals. Thereby, a signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier, and the pre-distorted output signal from the pre-distorter is forwarded to the power amplifier. Parameters of the pre-distorter are adapted based on an error between the linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm, and the linear system of equations formed by the direct learning algorithm are solved using a conjugate gradient algorithm, wherein, once per direct learning algorithm adaptation, at least one of the initial residual and the initial direction of the conjugate gradient algorithm are set based on the result of the previous adaptation.

Abstract: The present invention addresses method, apparatus and computer program product for controlling a Direct Learning Algorithm. Thereby, a power amplifier operating in a non-linear state is controlled. A signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier. The pre-distorted output signal is forwarded from the pre-distorter to the power amplifier. Parameters of the pre-distorter are adapted in plural steps based on an error between a linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm. It is detected whether the error diverges; and adapting of the parameters of the pre-distorter is stopped when it is determined that the error is diverging.

Abstract: The present invention addresses method, apparatus and computer program product for stabilization of the direct learning algorithm for wideband signals. Thereby, a signal to be amplified is input to a pre-distorter provided for compensating for non-linearity of the power amplifier, and the pre-distorted output signal from the pre-distorter is forwarded to the power amplifier. Parameters of the pre-distorter are adapted based on an error between the linearized signal output from the power amplifier and the signal to be amplified using an adaptive direct learning algorithm, and the linear system of equations formed by the direct learning algorithm are solved using a conjugate gradient algorithm, wherein, once per direct learning algorithm adaptation, at least one of the initial residual and the initial direction of the conjugate gradient algorithm are set based on the result of the previous adaptation.